Windows 7: Computer not Booting

I'm putting together a computer for a friend of mine, and having quite a few problems. I got everything put together and tried starting only to watch the lights turn on for a split second, start up the fan, then turn everything off.
We have tested the power supply, and that is working. Just to make sure, we bumped up the power to a 850 watt supply, which also gives the same problem. I have already checked and double checked the 24 pin motherboard connection, and the secondary 8 pin cpu power.



Once plugged in, the motherboard lights come on, and they stay on after the fans stop spinning. I can only think that the issue is with the motherboard, but am praying that is not the case.

The following is the diagnostic test I use for new builds that will not start. Follow the steps carefully and you can discover what component is causing the problem:

New System Failure Diagnostic

Basic diagnostic procedure is to uninstall the entire build and start over. Some people do this out of the case by placing the motherboard on an anti-static surface. This eliminates the possibility that there is a short circuit between the motherboard and the case through the connection posts (stand-offs). A standoff in the wrong location or a sloppy job will cause a short circuit on the motherboard.

The Test (power off, power cord unplugged):

• Disconnect everything externally connected except the mouse and keyboard (printers, USB devices, etc). If you are not using a wired mouse and keyboard see if you can borrow one. The wireless device is just another component you have to deal with.
• Disconnect the power and data cables from all the drives inside the computer (Hard drives, DVD/CD drives, etc).
• Remove all the cards installed in the expansion slots (PCI/PCI-e) including the video card. (Be careful handling them and place them on a non conductive surface while testing).
• Remove all the RAM sticks (same rules as above).
• You are now dealing with 3 components: Power Supply, Motherboard, Processor.
  

Now connect the power cord and turn the PC on.

• The motherboard should start beeping. You should get a beep code that tells you there is no memory. This is good, it means the processor is functioning and the motherboard is good so far.
• Now add one stick of memory in Slot A1 and power on. More beeping: the "no video card" beep code. This is good.
• Then add the video card and connect it to the monitor. You should get no beeping and you should see the BIOS start screens, ending with the message that there is no boot device.
• If you get no video then switch the one memory stick installed for another one and test.
• If you do get video then start adding components back, one at a time, until the system fails to boot. The last component you added is then the problem component.

Here are some troubleshooting steps from member TVeblen:

Strip it down and then add components back, one at a time, to try and isolate the offending component.

The test (power off, power cord unplugged):

• Disconnect everything externally connected except the mouse and keyboard (printers, USB devices). If you are not using a wired mouse and keyboard see if you can borrow one.

• Disconnect the power and data cables from all the drives inside the computer (Hard drives, DVD/CD drives).

• Remove all the cards installed in the PCI slots including the video card. (be careful handling them and place them on a non conductive surface while testing).

• Remove all the RAM sticks (same rules as above).

Now connect the power cord and turn the PC on.

• The motherboard should start beeping. You should get a beep code that tells you there is no memory. This is good, it means the processor is functioning and the motherboard is good so far.

• Now add one stick of memory in Slot A1 and power on. More beeping: "no video card" beep code. This is good.

• Then add the video card and connect it to the monitor. You should get no beeping and you should see the BIOS screens, ending with the message that there is no boot device.

If you get no video then switch the one memory stick installed for another one and test.

Continue adding components one at a time.

If at any point the PC fails the the last component added was the problem one.

If you removed everything and there is only the Motherboard (with integrated video), processor, and power supply to contend with and it does not POST or show anything on the screen, then the problem is one of those three.

If you have tested by using another power supply then you are down to two. CPUs rarely fail, so motherboard is the most likely guess.

Try performing a CLRTC or Clear CMOS as a last ditch effort, and check the 3v battery. Both long shots, but what do you have to lose at this point.

While thumbing through the motherboard book, I stumbled across a section explaining that while it does not have a normal post,it does have a series of leds to indicate a problem with a specific problem device. the cpu light comes on briefly before the fans stop. Is there anything else to try, or will i have to ship back the motherboard and order a new one?

If it helps at all, I'm using:
thermaltake tr2 rx 850w
asus p8z68-v
and an intel i7-2600k

What are the results of the troubleshooting steps mentioned earlier in this thread from both TVeblen and myself?

resetting the cmos has does nothing, nor has replacing the button cell battery. I am, however, a little confused about the clrtc.

Why didn't you go through all of the earlier steps?

You mean the ones that include the computer starting?
All the motehrboard lights start up and the cpu fan starts for half a second. Then it shuts off.
Even when narrowed down to the psu, motherboard, and cpu, this doesn't change.

It seems that I forgot one of the connections... Surprisingly, that was what was preventing it from running... Thank you for having me check again.

Not so surprisingly, that is how the diagnostic usually works. We always expect some big thing but in retracing our steps we find we missed some little thing.